Transducer Replacement

[Steve Olson]

My Hunter 34 is currently on the hard. One of the things I asked the yard to give me a quote for is to replace my old depth and speed transducers with my new Raymarine transducers (two total). Again, the boat is already out of the water. Even without running any wires, they're quoting me 6 hours ($600). Am I missing something? It seems like a pretty easy job. The yard allows me to do work there. Does anyone have any tips...or a YouTube video, perhaps?

Steve

[Cuttyhunk]

Are the new ones the same size (that might be a miracle!)? Do you have a solid hull or is it cored? Cored is a bigger job by far if you are drilling new holes.

[Greenhand]

Are these being placed in existing thu hulls? My instructor insists replacement can be done in the water, as long as you have a functioning bilge pump and several towels. As such, I assume it takes a couple of minutes. According to him, you just pop on out and the other one in...yeah, I won't be doing it in the water until I have had a chance to do it on the hard.

However, if the the thru hulls themselves are being removed, re-epoxied, redrilled, etc., the price you were quoted might be a bit more reasonable.

[CharlzO]

I think it's going to depend on the sizes involved. Being on the hard is a lot easier enough, but if the new units are smaller than the old, then there's having to build up the existing holes to support the new smaller transducers. If the new are larger, it's a lot easier (just drilling out a new, larger hole, and sealing it).

So on the one hand, 6 hours sounds like it might be overkill. But if there's a lot of glasswork to be done in the midst of it, possibly accurate. What are the sizes, and we can go from there.

[colemj]

Airmar, who makes the transducers that Raymarine uses, only make two sizes of thruhull for them - 1" and 2". Two inch is probably the most common.

It is very likely that your existing thruhull is the same size as your new transducers. If so, changing it out is very simple and fast. I just did one and it didn't take more than 1/2hr for removing the old one, cleaning the surfaces and reinstalling the new one.

In fact, there is a chance that your new transducers simply fit into your old thruhulls. Try this first - there will probably be indexing tabs that need to be the same, but if they are there, or can be moved, then you can just pop the new transducers into the old thruhulls.

My bet is at most, you have 30 minutes of work ahead of you.

Mark

[Roy M]

No job is too difficult for the man who doesn't have to do it.

[Greenhand]

Since you are allowed to work on your boat, could you give it a try and if you can't make it work, then you could schedule with them?

[Steve Olson]

Yeah, I just can't understand how they can justify 6 hours of labor, unless that includes about a 4 hour lunch. I'll head down to the boatyard after work and take a better look. I know they are at least approximately the same size. I have my fingers crossed that they are the exact same size.

[colemj]

How old are the old ones, and what brand of instruments were they hooked to? All bets are off if they are so ancient as to be those big metal external depth sounders and those propeller speed ones.

If not those, then they are either 1" or 2".

Mark

[Steve Olson]

Originally Posted by colemj

How old are the old ones, and what brand of instruments were they hooked to? All bets are off if they are so ancient as to be those big metal external depth sounders and those propeller speed ones.

If not those, then they are either 1" or 2".

Mark

I can't remember the brand, but they are the late 80's vintage. Without measuring, they look to be about the same size of the new ones.

[Gerrycooper56]

You mention the diameter but not the length - are they all the same?

[colemj]

Originally Posted by Gerrycooper56

You mention the diameter but not the length - are they all the same?

If this is addressed to me, no they are not all the same length, but that doesn't matter like diameter if one is replacing the thruhull. It does dictate whether an old thruhull can be reused.

Mark

[jeremiason]

When I had my C-36, I replaced both the Speed and Depth Transducers at my local boat yard, when I upgraded the electronics.

To save money we did a haul and hang during the boatyard lunch hour.

I took the nuts off the old transducers and banged them out with a 5 lbs sledge hammer.

The holes were the same dimension as the new Raymarine Transducers.

The new transducers went in with 5200 sealant and I was done in 50 minutes.

If they are quoting you six hours, unless there are other issues, they are out of their minds....

[Steve Olson]

Originally Posted by jeremiason

If they are quoting you six hours, unless there are other issues, they are out of their minds....

I think so too. I may use marine grade plywood pieces as backing plates for my new transducers. They also quoted me one hour to drop my keel and one hour to reinstall it. My friend and I did it on his Hunter just a couple of weeks ago and it took *maybe* 20 minutes, and we're not dockyard workers...so tomorrow I'm going to tackle the transducers and dropping the keel so the shaft can be removed/replaced. Those two things alone will save me almost $1k.

[Steve Olson]

Originally Posted by colemj

How old are the old ones, and what brand of instruments were they hooked to? All bets are off if they are so ancient as to be those big metal external depth sounders and those propeller speed ones.

If not those, then they are either 1" or 2".

Mark

The only ones are Signet. I wasn't able to make it down to the boat today, but I will tomorrow. Even if the new transducers are larger, I'm thinking I should be able to drill a new hole and install them fairly easily, since my boat is solid core. I'm planning on using 4200 and possibly 1/2" blocks of marine grade plywood as backing plates to provide extra support. Wish me luck!! haha